The Metadata Access Service is a user-managed service that allows the Developer tool to access Hadoop connection information to import and preview metadata. The Metadata Access Service contains information about the Service Principal Name (SPN) and keytab information if the Hadoop cluster uses Kerberos authentication. You can create one or more Metadata Access Services on a node. Based on your license, the Metadata Access Service can be highly available. Informatica recommends to create a separate Metadata Access Service instance for each Hadoop distribution. If you use a common Metadata Access Service instance for different Hadoop distributions, you might face exceptions.
HBase, HDFS, Hive, and MapR-DB connections use the Metadata Access Service when you import an object from a Hadoop cluster. Create and configure a Metadata Access Service before you create HBase, HDFS, Hive, and MapR-DB connections.